Mesoscopic investigation of the dynamic tensile behaviour of concrete from spalling test and implication on interpretation of test data

The dynamic tensile strength of concrete in spalling tests is usually evaluated through indirect measurements such as the pullback velocity at free-end surface specimen, instead directly measuring critical stress fractured plane(s) due to experimental constraints. These rely on several strong assumptions which could affect validity obtained spall data. This study presents numerical simulations test using a robust 2D mesoscale modelling framework, adopts ratedependant cohesive constitutive description. Beyond further investigation into mechanisms underlining increment observed from experiments, special attention paid traditional data processing approach, namely so called Novikov approximation, for deducing experiments. proposed model simulation firstly validated against evidences. Good agreements are achieved between and results terms pull-back free end cracking process. Based simulations, developed during section force, compared with based approximation. comparisons show marked discrepancies, raise questions about adequacy inferring thereby many existing tests. It argued that measured carries response information pre-peak damage history deviates basic assumption this approach. Accordingly, influences material heterogeneity, incident impact amplitude interface aggregates mortar investigated discussed. Results demonstrate approximation approach tends perform better under higher loading pulse ITZ strength, but it negatively affected by heterogeneity.